Search Results

Search found 22717 results on 909 pages for 'load operation'.

Page 121/909 | < Previous Page | 117 118 119 120 121 122 123 124 125 126 127 128  | Next Page >

  • What's the correct way to do a "catch all" error check on an fstream output operation?

    - by Truncheon
    What's the correct way to check for a general error when sending data to an fstream? UPDATE: My main concern regards some things I've been hearing about a delay between output and any data being physically written to the hard disk. My assumption was that the command "save_file_obj << save_str" would only send data to some kind of buffer and that the following check "if (save_file_obj.bad())" would not be any use in determining if there was an OS or hardware problem. I just wanted to know what was the definitive "catch all" way to send a string to a file and check to make certain that it was written to the disk, before carrying out any following actions such as closing the program. I have the following code... int Saver::output() { save_file_handle.open(file_name.c_str()); if (save_file_handle.is_open()) { save_file_handle << save_str.c_str(); if (save_file_handle.bad()) { x_message("Error - failed to save file"); return 0; } save_file_handle.close(); if (save_file_handle.bad()) { x_message("Error - failed to save file"); return 0; } return 1; } else { x_message("Error - couldn't open save file"); return 0; } }

    Read the article

  • Implementing eval and load functions inside a scripting engine with Flex and Bison.

    - by Simone Margaritelli
    Hy guys, i'm developing a scripting engine with flex and bison and now i'm implementing the eval and load functions for this language. Just to give you an example, the syntax is like : import std.*; load( "some_script.hy" ); eval( "foo = 123;" ); println( foo ); So, in my lexer i've implemented the function : void hyb_parse_string( const char *str ){ extern int yyparse(void); YY_BUFFER_STATE prev, next; /* * Save current buffer. */ prev = YY_CURRENT_BUFFER; /* * yy_scan_string will call yy_switch_to_buffer. */ next = yy_scan_string( str ); /* * Do actual parsing (yyparse calls yylex). */ yyparse(); /* * Restore previous buffer. */ yy_switch_to_buffer(prev); } But it does not seem to work. Well, it does but when the string (loaded from a file or directly evaluated) is finished, i get a sigsegv : Program received signal SIGSEGV, Segmentation fault. 0xb7f2b801 in yylex () at src/lexer.cpp:1658 1658 if ( YY_CURRENT_BUFFER_LVALUE->yy_buffer_status == YY_BUFFER_NEW ) As you may notice, the sigsegv is generated by the flex/bison code, not mine ... any hints, or at least any example on how to implement those kind of functions? PS: I've succesfully implemented the include directive, but i need eval and load to work not at parsing time but execution time (kind of PHP's include/require directives).

    Read the article

  • How to handle alpha in a manual "Overlay" blend operation?

    - by quixoto
    I'm playing with some manual (walk-the-pixels) image processing, and I'm recreating the standard "overlay" blend. I'm looking at the "Photoshop math" macros here: http://www.nathanm.com/photoshop-blending-math/ (See also here for more readable version of Overlay) Both source images are in fairly standard RGBA (8 bits each) format, as is the destination. When both images are fully opaque (alpha is 1.0), the result is blended correctly as expected: But if my "blend" layer (the top image) has transparency in it, I'm a little flummoxed as to how to factor that alpha into the blending equation correctly. I expect it to work such that transparent pixels in the blend layer have no effect on the result, opaque pixels in the blend layer do the overlay blend as normal, and semitransparent blend layer pixels have some scaled effect on the result. Can someone explain to me the blend equations or the concept behind doing this? Bonus points if you can help me do it such that the resulting image has correctly premultiplied alpha (which only comes into play for pixels that are not opaque in both layers, I think.) Thanks! // factor in blendLayerA, (1-blendLayerA) somehow? resultR = ChannelBlend_Overlay(baseLayerR, blendLayerR); resultG = ChannelBlend_Overlay(baseLayerG, blendLayerG); resultB = ChannelBlend_Overlay(baseLayerB, blendLayerB); resultA = 1.0; // also, what should this be??

    Read the article

  • What does setting the GL color before doing a texture mapping operation do?

    - by quixoto
    I am looking at some sample code in a book that creates a jittered antialiasing effect by repeatedly rendering a scene (at different offsets) onto a offscreen texture, then using that texture to repeatedly draw a quad in the main view with some blend stuff set up. To accumulate the color "correctly", the code is setting the color like so: glColor4f(f, f, f, 1); where f is 1.0/number_of_samples, and then binding the offscreen texture and rendering it. Since textures come with their own color and alpha data, what is the effect (mathematically and intuitively) that setting the overall "color" in advance achieves? Thanks.

    Read the article

  • How can I suspend \ resume the video caputre operation in v4l2 ?

    - by Ita
    Hi, I use the v4l2 api for video capture and image applying image processing algo' on each frame. I wish to be able to suspend the video capture. I see that there are 2 options for ioctling (new verb, its gonna catch) the stream. VIDIOC_STREAMON, VIDIOC_STREAMOFF will start and stop the stream. Is there a way to suspend \ resume it? Is this even necessary, or can I just use the start and stop controls with no extra processing time spent on creating the stream all over again ? Thank you for your time, Itamar

    Read the article

  • Can I make Thunderbird load different email accounts one after the other instead of all at the same

    - by Martin
    I use Thunderbird 3 on Vista. I use it for 3 POP accounts. When I start work in the morning, all three accounts are checked at the same time, and all emails are being loaded simultaneously. I think Thunderbird is quite slow in general, and this behaviour makes it even worse. At least it makes me feel so. Can I tell Thunderbird to check the accounts and load the emails one after the other?

    Read the article

  • Spring MVC: should service layer be returning operation specific DTO's ?

    - by arrages
    In my Spring MVC application I am using DTO in the presentation layer in order to encapsulate the domain model in the service layer. The DTO's are being used as the spring form backing objects. hence my services look something like this: userService.storeUser(NewUserRequestDTO req); The service layer will translate DTO - Domain object and do the rest of the work. Now my problem is that when I want to retrieve a DTO from the service to perform say an Update or Display I can't seem to find a better way to do it then to have multiple methods for the lookup that return different DTO's like... EditUserRequestDTO userService.loadUserForEdit(int id); DisplayUserDTO userService.loadUserForDisplay(int id); but something does not feel right about this approach. The reason do have separate DTO's is that DisplayUserDTO is strongly typed to be read only and also there are many properties of user that are entities from a lookup table in the db (like city and state) so the DisplayUserDTO would have the string description of the properties while the EditUserRequestDTO will have the id's that will back the select drop down lists in the forms. What do you think? thanks

    Read the article

  • What is the space character for the browser?

    - by Hiro Protagonist
    echo "\n\s\s\s\s\s\s" . "<div id='data-load' data-load='" . $load . "'></div>"; \n works for adding a return in...I tried \s logically for space but this does not work. Keep mind, I don't want this rendered in the browser view...but in the source view ( when you click view-source )...I'm trying to put my html in to a readable form. echo "&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp\n" . "<div id='data-path' data-path='" . $path . "'></div>"; This does not work either. I am composing HTML from PHP... echo " \n" . "<div id='data-load' data-load='" . $load . "'></div>"; This does not work either. Actual Code: public static function setUniversals() { $shared_object = new Shared(); if ( $shared_object->getLoadOn() == 1 ) { $load = 'server'; } else { $load = 'client'; } if( getcwd() === '/home/foo/public_html/develop' ) { $path = 'development'; } else { $path = 'production'; } $shared_object = new Shared(); echo "\n"; echo "\n " . "<div id='data-path' data-path='" . $path . "'></div>"; echo "\n " . "<div id='data-load' data-load='" . $load . "'></div>"; }

    Read the article

  • Can I do this?? Trying to load an object from within itself.

    - by Smikey
    Hi all! I have an object which conforms to the NSCoding protocol. The object contains a method to save itself to memory, like so: - (void)saveToFile { NSMutableData *data = [[NSMutableData alloc] init]; NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data]; [archiver encodeObject:self forKey:kDataKey]; [archiver finishEncoding]; [data writeToFile:[self dataFilePath] atomically:YES]; [archiver release]; [data release]; } This works just fine. But I would also like to initialise an empty version of this object and then call its own 'Load' method to load whatever data exists on file into its variables. So I've created the following: - (void)loadFromFile { NSString *filePath = [self dataFilePath]; if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) { NSData *data = [[NSMutableData alloc] initWithContentsOfFile:[self dataFilePath]]; NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data]; self = [unarchiver decodeObjectForKey:kDataKey]; [unarchiver finishDecoding]; } } Now this second method doesn't manage to load any variables. Is this line not possible perhaps? self = [unarchiver decodeObjectForKey:kDataKey]; Ultimately I would like to use the code like this: One viewController takes user entered input, creates an object and saves it to memory using [anObject saveToFile]; And a second viewController creates an empty object, then initialises its values to those stored on file by calling: [emptyObject loadFromFile]; Any suggestions on how to make this work would be hugely appreciated. Thanks :) Michael

    Read the article

  • Small website on Amazon EC2 Linux: a single large instance or more small instances in load balancing?

    - by Enrico Detoma
    I need to run a small website with a JSON webservice on Amazon EC2 Linux. The largest number of requests come from the JSON webservice, which provides some load in terms of MySQL queries. I'm trying to decide between two choices: A single large instance (Ubuntu 12.04 64-bit) with full LAMP stack or One or two small instances (Ubuntu 12.04 64-bit) with Apache/PHP only One small instance dedicated to MySQL (or RDS) Which setup would you consider to be more performant?

    Read the article

  • Performance of a get unique elements/group by operation on an IEnumerable<T>.

    - by tolism7
    I was wondering how could I improve the performance of the following code: public class MyObject { public int Year { get; set; } } //In my case I have 30000 IEnumerable<MyObject> data = MethodThatReturnsManyMyObjects(); var groupedByYear = data.GroupBy(x => x.Year); //Here is the where it takes around 5 seconds foreach (var group in groupedByYear) //do something here. The idea is to get a set of objects with unique year values. In my scenario there are only 6 years included in the 30000 items in the list so the foreach loop will be executed 6 times only. So we have many items needing to be grouped in a few groups. Using the .Distinct() with an explicit IEqualityComparer would be an alternative but somehow I feel that it wont make any difference. I can understand if 30000 items is too much and that i should be happy with the 5 seconds I get, but I was wondering if the above can be imporved performance wise. Thanks.

    Read the article

  • BASH Expression to replace beginning and ending of a string in one operation?

    - by swestrup
    Here's a simple problem that's been bugging me for some time. I often find I have a number of input files in some directory, and I want to construct output file names by replacing beginning and ending portions. For example, given this: source/foo.c source/bar.c source/foo_bar.c I often end up writing BASH expressions like: for f in source/*.c; do a="obj/${f##*/}" b="${a%.*}.obj" process "$f" "$b" done to generate the commands process "source/foo.c" "obj/foo.obj" process "source/bar.c "obj/bar.obj" process "source/foo_bar.c "obj/foo_bar.obj" The above works, but its a lot wordier than I like, and I would prefer to avoid the temporary variables. Ideally there would be some command that could replace the beginning and ends of a string in one shot, so that I could just write something like: for f in source/*.c; do process "$f" "obj/${f##*/%.*}.obj"; done Of course, the above doesn't work. Does anyone know something that will? I'm just trying to save myself some typing here.

    Read the article

  • What DNS server to use for dynamic load-balancing of website?

    - by Marki555
    I will have 2 servers in different datacenters (different countries) and I want to use DNS load-balancing mainly for High Availability of website hosted on those 2 servers. It is just ad tracking site, which records hit in local database and returns few lines on html code. I want to return 2 A records each time because of DNS pinning in browsers (if one server fails, browser will try second A record which it has already cached). Both servers will be acting also as DNS servers for redundancy. Now comes my proposed solution: I will use BIND and have both servers as a master for that zone. On each server there will be running script, which will periodically test availability (http) of both servers and remove IP from DNS in case of failure. Now the questions :) 1) Is BIND suitable for this solution? I think BIND performance is good and it is easy to manipulate the zone file via script. And as I will modify the zone only in case of failure/maintenance, the modifications (and thus bind reload) won't be often. 2) I plan to use TTL of 5 minutes. The website will have about 1000-3000 req/s but from distinct clients (each IP only 1-3 requests), so I think the DNS load won't be too much. I suppose their ISPs will cache the responses for those 5 mins. Is there any reason to lower the TTL even more? 3) Is my master-master approach good? Or should I make one of the servers master and the other one slave? Right now each server can monitor both itself and the other one. If only webservice fails, both DNS nodes will notice it. If the whole server fails, then the remaining DNS node will notice it and the failed node will not answer DNS queries anyway. 4) Is it a big issue when one NS server does not respond to queries? If yes, I can make a third DNS, so anytime at least 2 of them would accept queries... 5) Should I rewrite the zone file via script, or just use dynamic DNS update (for example via nsupdateutility)?

    Read the article

  • I cannot seem to load an XML document using ASP (Classic), IIS6. Details inside.

    - by carny666
    So I am writing a web application for use within my organization. The application requires that it know who the current user is. This is done by calling the Request.ServerVariables("AUTH_USER") function, which works great as long as 'Anonymous Access' is disabled (unchecked) and 'Integrated Windows Authentication' is enabled (checked) within IIS for this subweb. Unfortunately by doing this I get an 'Access Denied' error when I hit the load method of the XML DOM. Example code: dim urlToXmlFile urlToXmlFile = "http://currentwebserver/currentsubweb/nameofxml.xml" dim xmlDom set xmlDom = Server.CreateObject("MSXML2.DOMDocument") xmlDom.async = false xmlDom.load( urlToXmlFile ) ' <-- this is where I get the error! I've looked everywhere and cannot find a solution. I should be able to load an XML file into the DOM regardless of the authentication method. Any help would be appreciated. So far the only two solutions I can come up with are: a) create a new subweb that JUST gets the current user name and somehow passes it back to my XML reading subweb. b) open up security on the entire system to 'Everyone', which works but our IS department wouldn't care for that.

    Read the article

  • Why does a Linq Cast<T> operation fail when I have an implicit cast defined?

    - by Ryan Versaw
    I've created two classes, with one of them having an implicit cast between them: public class Class1 { public int Test1; } public class Class2 { public int Test2; public static implicit operator Class1(Class2 item) { return new Class1{Test1 = item.Test2}; } } When I create a new list of one type and try to Cast<T> to the other, it fails with an InvalidCastException: List<Class2> items = new List<Class2>{new Class2{Test2 = 9}}; foreach (Class1 item in items.Cast<Class1>()) { Console.WriteLine(item.Test1); } This, however, works fine: foreach (Class1 item in items) { Console.WriteLine(item.Test1); } Why is the implicit cast not called when using Cast<T>?

    Read the article

  • Is the Sleep operation no longer used in VBscript?

    - by Cheesus Toast
    The "Sleep" command as stated in many places over the internet (including here on this forum) DOES NOT WORK. Is it now an obsolete command? I am writing the VBScript code like this: sub button1_onclick() Wscript.Sleep 1000 div1.innerHTML = textbox1.value end sub It should wait 1 second and then execute that simple command. This is an utterly simple statement but it does not work. Plain and simple. It comes up with an error every time saying: Object Required: 'Wscript'

    Read the article

  • Can I use MPI_Probe to probe messsages sent by any collective operation?

    - by takwing
    In my code I have a server process repeatedly probing for incoming messages, which come in two types. One type of the two will be sent once by each process to give hint to the server process about its termination. I was wondering if it is valid to use MPI_Broadcast to broadcast these termination messages and use MPI_Probe to probe their arrivals. I tried using this combination but it failed. This failure might have been caused by some other things. So I would like anyone who knows about this to confirm. Cheers.

    Read the article

  • How to load kernel module at startup on FC9?

    - by dicroce
    I need to know how to automatically load a kernel module at startup on FC9. All the sites talk about adding an entry to /etc/modules.conf.... But that does not exist on FC9... Instead I have /etc/modprobe.d/ directory... Now, I suppose I need to put a file in this dir for my driver but I have no idea how to write this file... I just need "modprobe name" to be run...

    Read the article

  • Operation can only be performed on rows that belong to a DataGridView control?

    - by Behrooz
    it happens when i change the DataSource. i have checked everything(stack traces, all exception information, datasources, grids, all the threads, etc) i have also write lots of diagnostic code(+3000 line) it seems to be a virus, it is going to destroy everything in my app. all grids are going to have the very same error.(while i have not changed any of the code).wtf . it makes my datagridviews to have an red X on them.

    Read the article

< Previous Page | 117 118 119 120 121 122 123 124 125 126 127 128  | Next Page >